Functional Game Engine

FunGEn (Functional Game Engine) is a BSD-licensed, cross-platform, OpenGL/GLUT-based, non-FRP game engine/framework written in Haskell. Created by Andre Furtado in 2002, it's the oldest Haskell game engine, and with very few dependencies and two example games, it's one of the easiest ways to get started with Haskell game development. It provides:

I (Simon Michael) provide basic maintenance for this package. If you'd like to take it and run with it, or co-maintain, contact me. I'm sm on the #haskell-game IRC channel. On 2014/10/9 I moved it from darcs hub to github.


  (Latest available) API docs
  Andre's original pong tutorial
  Haskell wiki Game_Development
  Haskell wiki OpenGL tutorial

Discussion & help:
  #haskell-game IRC channel (join)
  FunGEn questions on Stack Overflow
  haskellgamedev reddit
  haskell-cafe mail list

Getting started

Install from hackage, run the examples:

$ cabal update
$ [cabal sandbox init]    # if needed, to avoid dependency problems
$ cabal install FunGEn
$ fungen-hello            # make sure ~/.cabal/bin or ./.cabal-sandbox/bin are in your PATH
$ fungen-pong
$ fungen-worms

Contribute patches:

$ git clone
$ cd fungen
$ cabal sandbox init         # if needed, to avoid dependency problems
$ cabal install              # install library and examples' data files
(Edit examples/pong/pong.hs)
$ cabal build fungen-pong && dist/build/fungen-pong/fungen-pong
(Commit, push, send pull requests)


What is a game engine?

A game engine can be considered as a library that provides game facilities to a game programmer. When using a game engine, the programmer must specify when the game events happen, rather than how they are implemented. A same functionality may have its implementation varying from platform to platform, in the case the engine is platform-independent. The main advantage of a game engine is that it can be reused to the development of many different kind of games, in an automated way, saving a lot of programming time.

Why Haskell?

We believe that Haskell is a great language to develop games, because of its high level of abstraction and the generation of a more concise, elegant and shorter code. This is great for code maintenance and understanding. Combining the power of Haskell with the facilities provided by game engines seems a promising project. You can find more info on Haskell in its official site.

What is HOpenGL?

HOpenGL stands for Haskell Open Graphics Library. Actually, it is a binding to one of the most famous graphics libraries around the world (OpenGL) and its auxiliary toolkit (GLUT). In other words, it makes possible to call OpenGL/GLUT routines (which were written in the C language) when programming in Haskell. You can find more info on HOpenGL in my HOpenGL Tutorial site, or in its official site.

To do

Andre's 2002 site included this message:

Current Status: Some feedback indicated that the first version of FunGEn was not as "functional" as it was desired: some game issues were still being dealt through an imperative fashion. This way, the authors of this project decided to change the game engine philosophy: programmers should describe a game as a set of "specifications" rather than defining its behavior imperatively. One plausible alternative for accomplishing this task is porting the Clean Game Library (CGL) to Haskell, adding some FunGEn specific features. Hence, this is the actual status of the FunGEn project: it is being rebuilt in order to provide game programming mechanisms following the CGL concepts. This really demands some time, but the authors expect a new version to be released soon.

... PLEASE NOTE: this is the very first version of FunGEn, and it was released just to get some feedback from game programmers. You are strongly invited to tell your game programming experiences with FunGEn, helping us to release a definitive, stable version). Ok, after this disclaimer, please fell yourself free to take a quick tour in the site; it contains a lot of useful information for those who are really interested in trying a new game programming experience. Nice coding...

and this todo list:

Here you have a list of some upcoming FunGEn features, and some other desired features (but with no implementation prevision yet).

Would you like to suggest a feature? Feel free to do it. Would you like to implement a feature? Please do it! Keep in touch.

and this old windows code with sound support.


Andre's 2002 credits:

FunGEn was created by Andre Furtado, Computation Science graduation student at the Informatics Center (CIn) of the Federal University of Pernambuco (UFPE), as part of a Scientific Iniciation (PIBIC/CNPq) research project (Creating a Game Platform Using Haskell), oriented by lecturer Andre Santos (PhD, 1995, University of Glasgow), who was responsible for figuring out a lot of FunGEn implementation details.

I would like to thank also the following people who contributed for the development of FunGEn:

FunGEn can be distributed freely, in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. I would thank you if you cite my name and this site if you are going to use FunGEn for other things besides home programming.